Pediatric heavy metal (particularly lead) poisoning is a widespread, yet preventable problem in many parts of the world.

Interior floor dust is found to be one of the major pathways of childhood exposure.

However, school and health authorities in most countries do not have any stipulations nor guidelines in regulating heavy metal contamination in floor dusts in schools.

This study attempts to examine the level of heavy metal contamination in 53 nursery schools and kindergartens in Hong Kong and study its relationship with the environmental factors.

The results of this study reveal that the arithmetic mean level of lead in exterior dust is 280.01 mg/kg, with a minimum level of 48.80 mg/kg and a maximum of 2108.31 mg/kg, which is somewhat lower than other studies, such as those reported by Chan et al. (Biomed.

Environ.

Sci. 1989 ; 2 :

Sci. 1989 ;

131-140) and Akhter and Madany (Water Air Soil Pollut. 1993 ;

66 : 111-119), but those of the manganese (x=532.16 mg/kg, range=102.51-1736.25 mg/kg) and zinc levels (x=2694.23 mg/kg, range=898.33-9899.85 mg/kg) are much higher.

Out of the 10 districts examined, Kwun Tong and North Point are found to be the most polluted.

They are older districts with polluting industries and heavy traffic.

The results of the analysis of variance suggest that the heavy metal particulate may originate from the exterior.